Inside the CSIRO’s hybrid energy systems hothouse

The CSIRO’s Centre for Hybrid Energy Systems is helping industry partners find the best mix of renewable energy generation and storage, and refining hydrogen and fuel cell technologies that may provide tomorrow’s baseload power.

If you think energy solutions are a bit like cake recipes, the CSIRO’s Centre for Hybrid Energy Systems is the test kitchen. A little bit of solar and a little bit of storage sounds simple enough, but what about temperature and humidity extremes? They’ll have a big effect on output. And of course, if you’re looking for fuel suitable for baseload generation there is always the possibility of filling LPG tanks with ammonia for export to Asia.

Who knew? You can learn a lot when you speak to a scientist.

At the Commonwealth scientists’ hybrid headquarters in Melbourne, the game is to combine two or more energy and storage technologies. The world is moving towards hybrid energy systems, says CSIRO Energy chief research scientist and research fellow Dr Sukhvinder Badwal (pictured). “You can combine any energy generation with storage.” The game gets hard when the options are so varied.
Solar PV is really only useful if it’s connected to the grid and some sort of storage system, Dr Badwal says. In a future where solar and storage are mainstream, energy management systems will make a big difference. “We are concentrating on the black box, what’s inside the black box and how the black box will interact with renewable energy systems,” he says.

Typically, people are looking at batteries at this stage for storage, but the CSIRO team is also looking at chemical energy storage rather than just electrical energy storage.

Sammy the simulator

To test hybrid systems the centre uses a simulator (connected to the grid and in-house solar) which can emulate a renewable energy profile anywhere around the world, and small-scale domestic applications up to 180kW. “With that type of system you can charge 1MWh battery with solar panels in a day,” Dr Badwal says.

The simulator can model results within a temperature range of -20 to 160 degrees Celsius and humidity between 0% and 100%. Once conditions are programmed into the simulator and it is connected to a battery, its performance and life is assessed. Batteries can also be connected to a hydrogen generation system, using water electrolysis. All sorts of scenarios are tested, such as batteries discharged in the morning, charged in the daytime and discharged again in the afternoon.

A power control monitoring system connects inputs and outputs to track how different systems perform under different conditions — and what an ideal system might be. “Rather than building a system separately each time you just plug and play and connect various systems in a hybrid mode,” Dr Badwal says.

The centre also runs an electrical and chemical energy storage module, with a range of different batteries and energy storage in the form of chemical, hydrogen and ammonia. The goal is to test the export potential for Australian renewable fuel energy. Dr Badwal cites the example of solar energy in the Pilbara region of Western Australia, “where there is plenty of sun”, to produce renewable energy into transportable fuel, such as ammonia, which can be shipped to Asia in containers similar to LPG containers. “We’re looking at the potential of exporting.”

Ammonia can be produced from hydrogen and nitrogen, where nitrogen is separated from air and hydrogen from water using solar PV electrolysis. Ammonia contains 17% hydrogen, which can be used in internal combustion engines and gas turbines. Because it becomes a liquid at very low pressure it is a very easy fuel to transport.

Baseload options

“We are also looking at the future,” Dr Badwal says, including energy products based on a hydrogen fuel cell. “For short run storage, batteries are quite good; if you need longer term storage … hydrogen is a very good solution. If you combine a fuel cell with a small battery, you can meet all your power requirements,” where a fuel cell can provide baseload power in the house and battery can fulfil peak load demand.

Among everything else going on in the energy market the mainstream acceptance of electric vehicles will be a major event. Unless chargers are connected to renewable sources of generation, cars will be charged with coal-fired plants, “so you only shift the emission levels somewhere else,” Dr Badwal says. “Unless we move to a large chunk of renewable energy in the grid we are not going to reduce emissions levels by moving to electric cars.”

Fast vehicle charging requires a lot of power: a 25kWh battery charged over half an hour requires 50kW of power. What sort of service stations will we have? Will they be connected to the grid or renewable energy sources and would battery storage be required? The CSIRO centre is setting up a small solar-powered charging station to learn what the future requirement is for a service station.

Whatever technology becomes commonplace in a world where the sun, wind or water power our lives, you can be sure it’s being tested in Melbourne today.